American Research Group (ARG) asked 1100 respondents 7/3-5/07:
Do you favor or oppose the US House of Representatives beginning impeachment proceedings against President George W. Bush?
The results found 45% in favor and 46% opposed, with 9% undecided.
Those are striking numbers, but deserve a bit of context.
First, as anyone would expect, there are sharp partisan divisions on this question, with 69% of Democrats, 50% of independents and 13% of Republicans support impeachment proceedings. One might wonder if 13% of Republicans supporting the impeachment of their president is really a credible estimate here. It seems large, given continued Republican support for President Bush in job approval in comparison to that of Democrats and independents.
Likewise, we might wonder if support for impeachment has risen in the immediate aftermath of the Libby sentence commutation.
ARG asked an impeachment question in a poll taken 3/13-15/06. Those results are shown in the top right panel of the plot. There the findings were 42% in favor and 49% opposed. (There was a slight difference in question wording as well.) In that March poll, 61% of Democrats, 47% of independents and 18% of Republicans favored impeachment. So this comparison suggests a small increase in support overall, and among Dems and independents, and a small DECREASE in support for impeachment among Republicans since the March survey. But these are modest changes, not large increases in impeachment sentiment.
One might also ask if the ARG survey results are typical of responses in other polls. There the answer is no, the ARG results show more support for impeachment than other polls do.
At the same time as the ARG March survey, Newsweek's poll taken 3/16-17/06, used a slightly different wording but found 26% in favor of impeachment, 69% opposed, well below the 42% ARG found at that time. Newsweek also found very low levels of support for impeachment among Republicans (5%) which seems more reasonable to me. Like ARG, the Newsweek survey found large partisan variation, though with less impeachment support in each partisan category than in the ARG survey (49% Dem, 23% Ind, 5% Rep.)
As for trend over time, the latest poll prior to the new ARG that asked about impeachment was a Time/SRBI poll taken 11/1-3/06, just before the election. That appears in the bottom right of the plot. Their results were 25% in favor, 70% opposed and 5% undecided, VERY similar to the March Newsweek results. Finally, the breakdowns by party in the Time/SRBI poll are also similar to the earlier Newsweek: 48% Dem, 22% Ind, and 4% Rep in favor of impeachment.
The conclusion is that there is little evidence for a substantial increase in support for impeachment, over the past 16 months, and the ARG results appear to be at the high end of support in comparison to other polling. It would be nice to have another new poll to compare with the current ARG results to see if this pattern has continued.